Antonio Conte put his players through their paces on Friday as the Chelsea squad prepared for their weekend clash with West Ham.
The Hammers have become a bogey team for Chelsea, who have won just two of their last seven meetings with their London rivals — losing three.
Chelsea cannot afford another slip on Sunday if they are to finish in the top four and qualify for next season's Champions League.
Conte's men start the weekend eight points behind fourth-placed Spurs, who beat them 3-1 at Stamford Bridge on April Fool's Day.